Computer and/or telecommunications components are often mounted in a rack and may be slidably connected to the rack so that individual ones of the components can be pulled out from the front of the rack for service or easier access. Many such components have cables connected to their rear portions, which cables may contain optical fibers or electrical wires. Care must be taken when sliding a component in and out of a rack that the cables do not become tangled with cables attached to other components or pinched between the moving component and another element. In the case of optical fibers the minimum bend radius of the fibers in the cable must not be exceeded as the cable flexes with the movement of the component. These problems may be avoided by mounting the component on a flat shelf surface and providing room on the shelf surface for holding an extra length of fiber to provide slack when the component moves. However, the slack cable on the shelf may not coil and uncoil properly when the component moves unless appropriate guiding structures are provided on the shelf. It would therefore be desirable to provide a support structure that supports and maintains cables in a desired configuration while the components connected to the cables move.